Prefabricated Roof Plate Element and Method for its Production

ABSTRACT

A prefabricated roof plate element (6) of the type comprising load-carrying girders in the form of longitudinal upper and lower steel frame parts placed at opposed sides of the roof plate element and corrugated at opposing upper and lower sides in longitudinal direction, where vertical side walls of said steel frame parts are interconnected by longitudinal connection plates (36) that form parts of said load carrying girders; and that said lower steel frame parts (4) furthermore are interconnected by an integral steel panel part (8) that forms the bottom of said roof plate element (6) and a ceiling of a building, respectively. The prefabricated roof plate element (6) is interconnected to other prefabricated roof plate elements (6) in a side-by-side manner to form a wider pre-fabricated roof plate element, the cavities of which are filled with insulation material, and are provided with a common top plate construction (70, 72) and a common roof foil covering (74).

FIELD OF INVENTION

The present invention relates to a prefabricated roof plate element ofthe type indicated in the preamble to claim 1.

The invention also relates to a prefabricated load carrying girderpreferably for use in prefabricated roof plate elements according to theinvention.

Furthermore, the invention relates to a method for the production ofprefabricated roof plate elements according to the invention.

BACKGROUND OF THE INVENTION

Prefabricated roof girders and roof plate elements, respectively, ofthis kind can be made totally from inorganic materials, which is verysignificant to durability and maintenance. Besides, it is of greatsignificance that the roof plate elements in question can have a freespan of up to 22 metres, i.e. one single roof plate element may cover inthe order of about 80 m², which of course is very essential with regardto reducing of the construction time and costs.

EP2145056A1 (WO2008/125109A1) discloses a prefabricated roof plateelement, including one or more longitudinal box-shaped roof girders thateach consists of two predominantly U-shaped steel sections which atmutually facing, open sides are interconnected along narrow outwardsbent lateral edges, the roof girders being connected at upper and lowernarrow sides corrugated in longitudinal direction with steel platescorrugated in transverse direction and having approximately the samewidth as the roof plate element, the roof girders/support girders androof plate element, respectively, designed with reduced height at an endpart intended to form eaves.

WO2012/113406A discloses a roof girder consisting of two predominantlyU-shaped steel sections, the lower and upper sides of which face eachother, and which is designed with narrow outwardly bent edges, the roofgirder at opposing upper and lower narrow sides are corrugated inlongitudinal direction, wherein the steel sections at the upper andlower open sides, respectively, are interconnected by means ofconnecting plates or partitionings which are fastened to substantial,substantially vertical sides of the steel sections in such a way thatthere is a spacing between the narrow outwardly bent edges of respectivelower and upper steel sections.

OBJECT OF THE INVENTION

On that background it is the purpose of the invention to provide a newand improved prefabricated plate-shaped roof element of the typeindicated in the preamble to claim 1 and by which may be provided bothcheaper and improved plate-shaped roof elements.

DESCRIPTION OF THE INVENTION

The prefabricated roof plate element according to the invention ischaracterised in, that vertical side walls of said steel frame partsbeing interconnected by longitudinal connection plates forming parts ofsaid load carrying girders, and that said lower steel frame partsfurthermore preferably being interconnected by an integral steel panelpart forming the bottom of said roof plate element and a ceiling of abuilding, respectively. By simple provisions is hereby achieved a newand improved prefabricated roof plate element, which furthermore may becheaper to produce.

It shall be emphasized that the fact that said lower steel frame partsbeing integrated with a steel panel parts forming the bottom of saidroof plate element means that the production of such roof plate elementsmay be carried out with a minimum of manual working hours—resulting inquicker and cheaper production and minimized prices.

The prefabricated roof plate element according to the invention maypreferably be such provided that it consists of a number of such uniformroof plate elements being interconnected side by side to form a widerprefabricated roof plate element, the cavities of which being filledwith insulation material, and afterwards being provided with a commontop plate construction and a common roof foil covering.

Appropriately, the prefabricated roof plate element according to theinvention is such provided, that said common top plate constructioncomprises steel panel plates provided with transverse corrugations andon top thereof semi-hard insulation plates and said common roof foilcovering.

Advantageously, the prefabricated roof plate element according to theinvention may be such provided, that said integral steel panel partforming the bottom of said roof plate element and a ceiling of abuilding, respectively, being provided with a large number ofperforations and possible an upper fabric cower to improve the acousticqualities of the bottom of said roof plate element.

Alternatively, the prefabricated roof plate element according to theinvention may be such provided, that said integral steel panel partforming the bottom of said roof plate element and a ceiling of abuilding, respectively, being provided with transverse corrugations toimprove the stiffness and carrying qualities of the bottom of said roofplate element.

Additionally, in order to improve the general stiffness and carryingcapacity it may be advantageous that the prefabricated roof plateelement according to the invention being such provided, that saidintegral steel panel part forming the bottom of said roof plate elementand a ceiling of a building, respectively, being provided withlongitudinal corrugations to improve the general stiffness and carryingqualities of the bottom of said roof plate element.

The invention also relates to a prefabricated load carrying girderpreferably for use in prefabricated roof plate elements according to theinvention, said prefabricated load carrying girder consisting oflongitudinal upper and lower steel frame parts being provided withlongitudinal corrugations to improve the general stiffness and carryingqualities of said load carrying girders, that vertical side walls ofsaid upper and lower steel frame parts being interconnected bylongitudinal connection plates, and that preferably plate-shapedinsulation material being inserted between said longitudinal connectionplates.

Hereby it becomes possible to build up plate-shaped roof elementsaccording to the invention in situ by means of a number of prefabricatedload carrying girders and by mounting said steel panel part forming thebottom of said plate-shaped roof element and a ceiling of a building,respectively. Preferable, the in situ mounted combined button andceiling plates may be provided with longitudinal or transversecorrugations to improve the general stiffness and carrying qualities ofsaid bottom of said plate-shaped roof element.

Afterwards, the upwardly open central hollowness of the in situ build upplate-shaped roof element is filled with a suitable insulation material,before the plate-shaped roof element is closed upwardly by means oftransversely corrugated steel panels, and finally upper semi-hardinsulation plates and an uppermost roof foil covering being mounted onthe corrugated steel panels.

Furthermore, the invention relates to a method for the production ofprefabricated roof plate elements comprising the following method steps:

a thin steel blank having a total width similar to that of thesummarised partial width of the respective wall parts of a lower steelplate frame part to be bend up is continuously unrolled from a supplyroll as the middle part of said thin steel blank adapted to form acentral lower bottom part of said lower steel plate frame and a ceilingin a building,

opposed end parts of said steel blank being continuously bend up to format least lower longitudinal corrugations and lower, vertical sidepanels,

a thin steel blank having the total width similar to that of upper steelplate side frame parts to be bend up is continuously unrolled fromanother supply roll,

opposed end parts of said last mentioned steel blank being continuouslybend up to form at least upper longitudinal corrugation and upper,vertical side panels,

longitudinal vertical connection plate members being situated in saidlongitudinal corrugation and being interconnected between said upper andlower vertical side panels to form an upwardly open girder-likeconstruction,

more of such upwardly open girder-like constructions may beinterconnected side by side to create a wider roof plate element ofwhich the upwardly open cavities are filled with insulation material,

said wider roof plate element being closed upwardly by means oftransverse corrugated steel panels and on top thereof by means of commonsemi-hard insulation plates and a common roof foil covering.

Alternatively the method according to the invention may comprise furthermethod steps:

a thin steel blank having a total width similar to that of the steelplate frame part to be bend up is continuously unrolled from a supplyroll as the middle part of said thin steel blank adapted to form acentral lower bottom part of said steel plate frame being provided witha large number of perforations, said lower bottom part at a side facingupwards being provided with an upper fabric cower to improve theacoustic qualities of the bottom of said roof plate element as well as asteam tight membrane.

According to a further alternative the inventive method could comprisefurther method step:

that said interconnection between said vertical side panels of therespective upper and lower steel plate frame and said longitudinal,vertical connections plate panels is carried out by one or more of thefollowing connecting means or methods: Screws, clinching, gluing,assembling of combined sealing lips and profiles or welding.

A still further method according to the invention may comprise thefurther method steps:

a thin steel blank having a total width similar to that of the steelplate frame part to be bend up is continuously unrolled from a supplyroll as the middle part of said thin steel blank adapted to form acentral lower bottom part of said steel plate frame being provided withlongitudinal corrugations to improve the free span carrying capacity ofa roof plate element provided by interconnection side by side a numberof such upwardly open steel plate frame parts etc.

DESCRIPTION OF THE DRAWING

The prefabricated roof plate element according to the invention isdescribed in more details in the accompanying drawing—in which:

FIG. 1 shows a plane schematic sectional view illustrating a preferredembodiment of a method for the production of prefabricated plate-shapedroof element according to the invention may be produced,

FIG. 2 shows a plane schematic view illustrating an other embodiment ofa method of the production of prefabricated plate-shaped roof elementmade from more side by side interconnected roof elements as shown inFIG. 1,

FIG. 3 shows a perspective view illustrating another embodiment of amethod for the production of steel plate frame parts for a prefabricatedplate-shaped roof element according to the invention,

FIG. 4 shows a perspective view illustrating how steel plate frame partsas shown in FIG. 2 at opposite sides being provided with a pair oflongitudinal connection element members interconnecting the respectivesteel plate frame parts,

FIG. 5 shows a perspective view of the illustrating how the steel plateframe parts of the plate-shaped roof element as seen in FIG. 4afterwards are filled with a block of insulating material,

FIG. 6 shows a plane sectional view of a modified embodimentplate-shaped roof element provided at opposite sides with only onelongitudinal connection members between the respective steel frameparts,

FIG. 7 shows a perspective view of a rather narrow plate-shaped roofelement having a cross section as that of the modified plate-shaped roofelement of FIG. 6,

FIG. 8 shows a perspective view illustrating in principle an embodimentof a method for the production of steel plate frame parts for aprefabricated plate-shaped roof element similar to that of FIG. 3according to the invention,

FIG. 9 shows a perspective view of a further embodiment of a steel plateframe for a plate-shaped roof element where the interconnections betweenthe respective steel sections at opposite sides being provided betweennarrow inwardly bend edges of the steel sections,

FIG. 10 shows a perspective view of a further embodiment of alongitudinal steel plate frame for a plate-shaped roof element, wherethe lower plate portion being provided with longitudinal reinforcementcorrugations,

FIG. 11 shows a perspective view of an enlarged end portion of the steelplate frame shown in FIG. 10,

FIG. 12 shows a perspective view of an embodiment for a narrow,longitudinal girder for a plate-shaped roof element according to theinvention,

FIG. 13 shows a perspective view of a lower steel plate frame portionsimilar to that shown in FIG. 8,

FIG. 14 shows a perspective view of a modified embodiment for lowersteel plate frame portion provided with transverse corrugations,

FIG. 15 shows a perspective view of a further modified embodiment for alower steel plate frame portion provided with longitudinal corrugations,

FIG. 16 shows a perspective, partial view of an embodiment for aplate-shaped roof element according to the invention consisting of threeassembled plate-shaped roof plate elements as seen in FIG. 5,

FIG. 17 shows a perspective, partial view of the plate-shaped roofelement shown in FIG. 16 and provided with upper, transverse corrugatedsteel plate profiles,

FIG. 18 shows a perspective, partial view of the plate-shaped roofelement shown in FIG. 17 and provided with upper semi-hard plate ofinsulating material,

FIG. 19 shows a perspective, partial view of the plate-shaped roofelement shown in FIG. 18 and further provided with an uppermost rooffolio material,

FIG. 20 shows a perspective view of the plate-shaped roof elementaccording to the invention as shown in FIGS. 16-19—as seen from below,

FIG. 21 shows a plane sectional view through the plate-shaped roofelement shown in FIGS. 16-20,

FIG. 22 shows a perspective view of the plate-shaped roof elementaccording to the invention as shown in FIGS. 16-19—as seen from above,

FIG. 23 shows a perspective view of an enlarged end portion of the steelplate frame similar to that shown in FIG. 11 and provided with an endclosing panel,

FIG. 24 shows a perspective view of an enlarged end portion of the steelplate frame similar to the lower frame portion shown in FIGS. 8 and 9,

FIG. 25 shows a perspective view of an enlarged end portion of an upperside part of the steel plate frame shown in the left hand side of FIG.3,

FIG. 26 shows a perspective view of an enlarged end portion of an upperside part of the steel plate frame shown in the right hand side of FIG.3,

FIG. 27 shows a perspective view of an enlarged end portion of a lowerside part of the steel plate frame shown in the left hand side of FIG.8,

FIG. 28 shows a perspective view of an enlarged end portion of an upperside part of the steel plate frame shown in the left hand side of FIG.8,

FIG. 29 shows a perspective view of an end part of a prefabricated roofelement provided with an inclined end part intended to form eaves,

FIG. 30 show a plane side view of the end part shown in FIG. 29,

FIG. 31 shows a perspective view of an end part of a prefabricated roofelement provided with a reduced height at an end part intended to formeaves,

FIG. 32 shows a plane side view of the end part shown in FIG. 31,

FIG. 33 shows a perspective view of an end part of a prefabricated roofelement provided with a reduced height at an end part intended to formeaves,

FIG. 34 shows a plane side view of the end part shown in FIG. 33,

FIG. 35 shows a plane sectional view of another embodiment of aplate-shaped roof element according to the invention,

FIGS. 36A-36C show plane sectional views through embodiments of carryinggirders for use in plate-shaped roof elements according to theinvention,

FIGS. 37A-37C show plane sectional views through further embodiments ofcarrying girders for use in plate-shaped roof elements according to theinvention,

FIG. 38 shows a perspective view of a plant for the continuouslyproduction of load carrying girders according to the invention,

FIG. 39 shows a perspective view of an embodiment for a profile pressstation for bending up upper and lower steel frame profiles for loadcarrying girders according to the invention,

FIG. 40 shows a plane top view of the production plant shown in FIG. 38,

FIG. 41 shows a perspective view of the assembling details of theproduction plant shown in FIG. 38, and

FIG. 42 shows a perspective view of a cutting station of the productionplant shown in FIG. 38.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates how an embodiment of a longitudinal carrying steelframe 4 for a plate-shaped roof element 6 continuously is bended-up froma thin steel blank 2, as the latter being unrolled from a not shownsupply roll.

The total width of said steel blank 2 corresponds to the summarisedlengths of the respective partial wall parts of at least a longitudinallower steel frame part 8.

From a narrow thin steel blank are upper left and right hand sideplate-shaped frame parts 10 and 12 continuously bend-up, beforelongitudinal narrow bend-in edges 14 being interconnected with similarlongitudinal narrow bend-in edges 16 of said lower steel frame part 8.

In order to prevent or reduce thermal bridges between said narrowbend-in edges 14, 16 special sealant tapes may be positioned betweensaid narrow bend-in edges 14, 16 before said interconnection of theseparts.

FIG. 2 shows a wider, lower steel frame 18 build-up by interconnectingside by side three of said lower steel frame parts 8.

According to an important aspect the building-up of the plate-shapedroof element 2 may be provided in a mobile factory arranged in one ormore containers.

In order to maintain correct vapour barrier effect of such buildtogether frame parts 8 special sealant tapes may be used between thelower external side parts of said lower frame parts 8. Such specialsealant tapes may furthermore comprise electric leads for activation theadhesive effect of said special sealant tapes between said lowerexternal side parts of the frame parts 8.

Alternatively, said longitudinal narrow bend-in edges 14, 16 may besubstituted by narrow bend-out edges such that said interconnections areplaced at the outside of said plate-shaped element 6 and the interiorlongitudinal joints would be quite plane without disturbing projectingparts such that it would be possible to make use of interiorlongitudinal connection plate members 36 as described by laterembodiments according to the invention.

FIG. 3 shows an alternative embodiment for a longitudinal carrying steelframe 20 by which lower left and right hand side vertical side wallpanels 22 and 24 are plane i.e. without the above mentioned inwardlybend narrow edges 16. In a corresponding manner upper left and righthand side steel frame parts 26 and 28 are also made with plane verticalside wall panels 30 and 32.

FIG. 4 shows how a girder-like construction 34 is made by situatinglongitudinal, vertical connection plate members 36 in upper and lowerlongitudinal corrugations 38, 40 of the respective upper and lower wallparts 42 and 44 of said longitudinal carrying steel frame 20.

Furthermore, outermost of said longitudinal connection plate members 36are positively connected with the respective vertical side walls panels22, 24 and 30, 32, while innermost of said longitudinal connection platemembers 36 being situated in innermost upper and lower corrugations ofthe respective upper and lower wall parts 42 and 44 of said longitudinalcarrying steel frame 20.

Furthermore, innermost narrow, vertical side wall panels 46 and 48 ofsaid upper left and right hand side steel frame parts 28 and 30 may bepositively connected along the interior upper side edges of saidinnermost of said longitudinal connection plate members 36.

Said positive connections between said vertical side panels of therespective upper and lower steel plate frame and said longitudinal,vertical connection plate members 36 including said interconnection ofsaid inwardly bended short edges are carried out by one or more of thefollowing connecting means or methods: Screws, clinching, gluing,assembling of combined sealing lips and profiles or welding.

Furthermore, FIG. 4 shows that the longitudinal narrow cavities 50between the longitudinal connection plate members 36 are filled with asuitable insulating material. The same is the case in FIG. 5, where thecentral cavity 52 of the longitudinal carrying steel frame 20 is filledwith a suitable insulation material.

FIG. 6 shows a plane sectional view of an alternative embodiment for alongitudinal carrying steel frame part 54, where only longitudinalconnection plate members 56 being provided between the outermostrespective upper and lower corrugations 58, 60, while the central cavityagain is filled with a suitable insulating material 62, while FIG. 7shows a perspective view of said longitudinal carrying steel frame part54.

FIGS. 8 and 9 show perspective views of an embodiment for a longitudinalcarrying steel frame 4 similar to that of FIG. 1, that is wherelongitudinal narrow bend-in edges 14 of upper left and right hand sideplate-shaped frame parts 10 and 12 of a plate-shaped roof element 6being interconnected with similar longitudinal narrow bend-in edges 16of said longitudinal lower steel frame part 8.

FIG. 10 shows a perspective view of a further embodiment for alongitudinal carrying steel frame 57, where a bottom part 58 in order toimprove the general load carrying capacity is provided with longitudinaldirected corrugations 60. FIG. 11 shows an enlarged view of an endportion of said longitudinal carrying steel frame 57.

FIG. 12 shows a perspective view of an alternative longitudinalgirder-like construction 63 built-up of two uniform but inverted steelplate profiles 64 having upper and lower longitudinal corrugations 66which being interconnected a number of longitudinal connection platemembers 36, two of which being present at opposed sides of saidgirder-like construction 63.

Advantageously, said connection plate members 36 may exist of so-calledPower Board® consisting of inorganic, fireproof composite material suchas Perlite (MgO) reinforced with more layers of glass fibre netting.Said Power Board® being available in standard size of 1220×2440 mm, fromwhich said connection plate members 36 may be cut with suitable heightand lengths.

By the mounting of said connecting plate members 36 vertical jointsbetween adjoining connecting plate members are mutually displaced andthe connection plate members are connected to each others and tovertical plate portions of said inverted steel plate profiles 64 and therespective side parts of said longitudinal corrugations 68—preferably bygluing. Between said longitudinal connection plate members 36 is bygluing interconnected a layer of semi-hard insulation material.

According to an alternative embodiment said longitudinal plate member 36may be substituted by other plate material having low thermalconductivity—such as stainless steel.

This alternative girder-like construction 63 may be built-in betweenlongitudinal carrying steel frames 20 according to the invention inorder to provide for an alternative manner of improving the carryingcapacity and length of free span of prefabricated roof plate elements 6according to the invention.

Furthermore, said alternative girder-like construction 63 may be used asa standard carrying girder in order to substitute more expensivelaminated wooden girders or the like.

FIG. 13 shows an enlarged perspective view of a lower steel plate frameportion 4 similar to that shown in FIG. 8, where a central bottom partbeing provided with a large number of perforations 67 and possibleprovided with an upper fabric cower 68 to improve the acoustic qualitiesof the bottom part of said roof plate element 6. In this connection itis very important that a suitable vapour barrier is arranged directlyabove said upper fabric cower 68 at the upper side of said centralbottom part.

FIG. 14 shows an enlarged perspective view of a modified embodiment forlower steel plate frame portion provided with transverse corrugations69, while FIG. 15 shows a perspective view of a further modifiedembodiment for a lower steel plate frame portion provided withlongitudinal corrugations 60.

FIG. 16 shows an enlarged perspective view of a part of an embodimentfor a plate-shaped roof element 6 according to the invention consistingof three assembled plate-shaped roof plate elements 20 as seen in FIG.5.

FIG. 17 shows an enlarged perspective, partial view of the prefabricatedplate-shaped roof element 6 shown in FIG. 16 and provided with upper,transverse corrugated steel plate profiles 70, while FIG. 18 shows anenlarged perspective, partial view of the plate-shaped roof element 6shown in FIG. 17 and provided with upper semi-hard plates 72 ofinsulating material, and finally FIG. 19 shows an enlarged perspective,partial view of the plate-shaped roof element 20 shown in FIG. 18 andfinally provided with an uppermost roof folio covering 74.

FIG. 20 shows a perspective view of the plate-shaped roof element 6according to the invention as shown in FIGS. 16-19—as seen from below,while FIG. 21 shows a plane sectional view through the plate-shaped roofelement 6 shown in FIGS. 16-20, while FIG. 22 shows a perspective viewof the plate-shaped roof element 6 according to the invention as shownin FIGS. 16-19—as seen from above,

FIG. 23 shows a perspective view of an enlarged end portion of the steelplate frame 57 similar to that shown in FIG. 11 and provided with an endclosing panel 76, while FIG. 24 shows a perspective view of an enlargedend portion of the steel plate frame similar to the lower frame portion8 shown in FIGS. 8 and 9.

FIG. 25 shows a perspective view of an enlarged end portion of an upperside part of the steel plate frame 26 shown in the left hand side ofFIG. 3, while FIG. 26 shows a perspective view of an enlarged endportion of an upper side part of the steel plate frame 28 shown in theright hand side of FIG. 3.

FIG. 27 shows a perspective view of an enlarged end portion of a lowerside part of the steel plate frame 8 shown in the left hand side of FIG.8, and FIG. 28 shows a perspective view of an enlarged end portion of anupper side part of the steel plate frame 10 shown in the left hand sideof FIG. 8.

The general width of each of said longitudinal steel plate frames 8, 20,34, 54 is between 500 and 1500 mm, whereby the total width of threeinterconnected longitudinal steel plate frames may vary from 1500 and4500 mm, normally the maximum with allowed for road transportation mayvary from 3000-3600 mm

The height of the side panels of the lower steel plate frame 8comprising the longitudinal bend-in edges 14, 16 (FIGS. 1 and 2) mayvary from 50-200 mm, while the height of the upper left and right handside panels 10, 12 may vary from 50-500 mm.

The height of the side panels 30, 32 of the upper longitudinal steelplate frames 26, 28 (FIG. 3) may be about 150 mm, while the height ofthe side panels 22, 24 of the lower longitudinal steel plate frame 20may be about 100 mm.

As mentioned above a prefabricated roof plate element 6, as shown inFIGS. 16-22, may preferable consist of three interconnected side by sidelongitudinal steel plate frames 20 (FIG. 5). The production beingpreferably organized in such a manner, that in three separate productionlines said longitudinal steel plate frames 20 are produced and thecavities thereof being filled with insulation material.

At the ends of said three lines predetermines lengths of saidlongitudinal steel plate frames 20 are moved transversely against eachother for said interconnection side by side by gluing or by otherconnecting means, before mounting said transverse metal profiles 70 ontop of the already interconnected longitudinal steel plate frames 20 toform a plate-shaped roof plate element 6. Then semi-hard insulationplate members 72 and finally on top thereof is mounted a roof foilcovering 74.

FIG. 29 shows a perspective view of an end part 78 of a prefabricatedroof element 80 provided with inclined end parts 82 intended to forminclined eaves 84, while FIG. 30 shows a plane side view of the end part78 shown in FIG. 29.

FIG. 31 shows a perspective view of an end part 86 of a prefabricatedroof element 88 provided with a reduced height at an end part 90intended to form upper eaves 92, while FIG. 32 shows a plane side viewof the end part 86 shown in FIG. 31.

FIG. 33 shows a perspective view of an end part 94 of a prefabricatedroof element 96 provided with a reduced height at an end part 98intended to form lower eaves 100, while FIG. 34 shows a plane side viewof the end part 94 shown in FIG. 33.

FIG. 35 shows a plane sectional view through an alternative embodimentfor a plate-shaped roof element 102 according to the invention, wherethe roof element 102 is built up by means of two load carrying girders104—each consisting of upper and lower corrugated frame profiles 106,108 bend up from thin steel plate, and where longitudinal vertical edgeparts 105, 107 being interconnect by means of rigid connection plates110 as the hollowness between said connection plates 110 being filledwith semi-hard plate-shaped insulation material 112.

Afterwards, said girders—possible in situ—being interconnected with alower bottom plate member 114 formed the ceiling in the building inquestion, and finally the hollowness between the load carrying girders104 being filled with a suitable insulation material, before theplate-shaped roof element 102 being closed upwardly by means of possibleprofiled steel plates and a suitable roof foil covering.

Preferably, said connections between said vertical edges 105, 107 andthe rigid connection plates 110 being made by suitable gluing.

FIGS. 36A-C and FIGS. 37A-C showing cross sections illustrating sixdifferent widths and heights of said load carrying girders 104, which inpractice may vary considerably.

FIGS. 38 and 40 show a perspective and a plane view, respectively, of anembodiment of a production plant 120 for the continuously production ofload carrying girders 104, where initially upper and lower frameprofiles 106, 108 successively being bend up from straight steel bandsat the profile press station 122. The direction of production is markedwith an arrow 118.

Then the rigid connection plates 110 at both sides of a semi-hardplate-shaped insulation material 112 are assembled with the upper andlower corrugated frame profiles 106, 108 by means of suitable gluing(FIG. 41)—before the assembled load carrying girder member 125 supportedon a roller conveyor 126 is let through a hardening station 124—afterthe hardening station 124 the assembled load carrying girder member 125arrive to a cutting station 128 (FIG. 42)—where the final predeterminedlength of the load carrying girders 104 are adjusted.

As mentioned above an important aspect of the present invention is thepossibility that the in situ production of both load carrying girders104 and the assembling of prefabricated plat-shaped roof elements may beorganized by means of a mobile productions plan build-up in one or morecontainers.

REFERENCE NUMERALS FROM THE DRAWING

-   2 thin steel blank-   4 longitudinal carrying steel frames-   6 prefabricated plate-shaped roof element-   8 longitudinal lower steel frame part-   10 upper left hand side plate-shaped frames-   12 upper right hand side plate-shaped frames-   14 upper narrow bend-in edges-   16 lower narrow bend-in edges-   18 wider lower steel frame-   20 longitudinal carrying steel frames-   22 lower left hand side vertical side panels-   24 lower right hand side vertical side panels-   26 upper left hand side steel frame part-   28 upper right hand side steel frame part-   30 left vertical side wall panels-   32 right vertical side wall panels-   34 girder-like constructions-   36 longitudinal, vertical connection plate members-   38 upper longitudinal corrugations-   40 lower longitudinal corrugations-   42 upper wall parts of 20-   44 lower wall parts of 20-   46 left hand side innermost side wall panels-   48 right hand side innermost side wall panels-   50 narrow cavities between connection plate members-   52 central cavities of 20-   54 alternative embodiment longitudinal carrying steel frame part-   56 longitudinal connection plate members-   57 alternative longitudinal carrying steel frames-   58 upper longitudinal corrugations-   60 lower longitudinal corrugations-   62 suitable insulation materials-   63 girder-like constructions-   64 uniform inverted plate profiles-   66 upper and lower longitudinal corrugations-   67 perforations-   68 upper fabric cower-   69 transverse corrugations-   70 upper transverse corrugated steel profiles-   72 semi-hard insulation materials-   74 uppermost roof foil material-   76 end closing profile-   78 end part of prefabricated roof element-   80 prefabricated roof element-   82 inclined end part-   84 eaves-   86 end part of prefabricated roof element-   88 prefabricated roof element-   90 end part with reduced height-   92 eaves-   94 end part of prefabricated roof element-   96 prefabricated roof element-   98 end part with reduced height-   100 eaves-   102 plate-shaped roof element-   104 load carrying girder-   105 upper vertical edges-   106 upper corrugated frame profile-   107 lower vertical edges-   108 lower corrugated frame profile-   110 rigid longitudinal connection plates-   112 semi-hard plate-shaped insulation material-   114 lower button plate member-   118 direction arrow-   120 production plant-   122 profile press station-   124 hardening station-   125 load carrying girder member-   126 roller conveyor-   128 cutting station

1-11. (canceled)
 12. A method for production of a prefabricatedload-carrying girder comprising the steps of: (a) providing two straightsteel blanks; (b) bending the two straight steel blanks at a profilepress station into upper and lower corrugated frame profiles havingrespectively upper and lower corrugations; (c) providing two rigidconnection plates and a semi-hard plate-shaped insulation material; (d)assembling the rigid connection plates at both sides of a semi-hardplate-shaped insulation material with the upper and lower corrugatedframe profiles into an assembled load-carrying girder member by gluing;(e) hardening the assembled load-carrying girder member at a hardeningstation; and (f) cutting the assembled load-carrying girder member at acutting station to a predetermined length, whereby the load-carryinggirder member is produced.
 13. The method for production of aprefabricated load-carrying girder according to claim 12, wherein therigid connection plates consist of a composite material reinforced withlayers of glass fibre netting.
 14. The method for production of aprefabricated load-carrying girder according to claim 12, wherein thesteps (e) and (f) are performed along a roller conveyor.
 15. The methodfor production of a prefabricated load-carrying girder according toclaim 12, wherein steps (a) to (f) are performed along a rollerconveyor.
 16. The method for production of a prefabricated load-carryinggirder according to claim 12, wherein in step (d) the semi-hardplate-shaped insulation material is engaged in the upper and lowercorrugations of the respective upper and lower corrugated frameprofiles.
 17. The method for production of a prefabricated load-carryinggirder according to claim 12, wherein steps (a) to (f) are performedin-situ.
 18. A method for production of a prefabricated roof plateelement comprising the steps of: producing a plurality of prefabricatedload-carrying girders according to claim 12, and interconnecting atleast two of the plurality of prefabricated load-carrying girders with alower bottom plate member, thereby forming a hollowness between theload-carrying girders.
 19. The method for production of a prefabricatedroof plate element according to claim 18, including a step of fillingthe hollowness with an insulation material.
 20. A load-bearing girderfor use in making a roofing plate element, said girder comprising: asteel upper frame member providing a corrugated top wall and adownwardly-extending outer side panel, a steel lower frame partproviding a corrugated bottom wall and an upwardly-extending outer sidepanel, and two structural plate members extending between aligned andfacing corrugations in the top wall and the bottom wall.
 21. Theload-bearing girder according to claim 20, wherein a first of said twostructural plate members is connected to the downwardly-extending outerside panel and to the upwardly-extending outer side panel.
 22. Theload-bearing girder according to claim 21, wherein the steel upper framemember provides a downwardly-extending inner side panel, the steel lowerframe part provides an upwardly-extending inner side panel, and a secondof said two structural plate members is connected to thedownwardly-extending inner side panel and to the upwardly-extendinginner side panel.
 23. The load-bearing girder according to claim 22,including insulation material between the first and second platemembers.
 24. The load-bearing girder according to claim 20, wherein eachof the structural plate members is substantially flat.